// TypeScript（TS）是JavaScript（JS）的超集，增加了静态类型检查
//作业:":"后面能不能有更多类型的
var age1 = 18;
var name1 = "zs";
var isOK;
console.log(typeof age1);
console.log(typeof name1);
console.log(name1.toUpperCase());
// age1 = "HELLO";
name1 = "list";
isOK = false;
// console.log(age1.toUpperCase()); 
function changeNameToUpper1(xxx) {
    var a = xxx.toUpperCase();
    // console.log(a);
    return a;
}
// 调用函数并接收返回值
var res3 = changeNameToUpper1(name1);
console.log(res3);
var res2 = changeNameToUpper1("hello");
console.log(res2);
